Centrifugal switch



Feb. 23 1926. 1,574,370

H. E. CURTISS CENTRI'FUGAL SWITCH Filed August 25l 1924 W I j me/nto@ Patented Feb. 23, 1.926.

UNITED STATES HAROLD E. CURTISS, OF MONROE, MICHIGAN.

CENTRIFUGAL SWITCH.

Application led August 25, 1924. Serial No. 734,045.

To all whom it may concern:

Be it known that I, HAROLD E. CURTISS, a citizen of the United States, residing at Monroe, in the county of Monroe and State of Michigan, have invented certain new and useful Improvements in Centrifugal Switches, of which the following is a speci.- fication.

This invention relates to an improved automobile signal, and it has particular reference to a speed indicating signal, which I have devised to assist automobile drivers to determine the approximate speed of travel of a leading vehicle.

A device of this class is also useful to enable traflic oflicers to determine whether or not a machine is travelling at a speed not permitted by law.

The invention has more specific reference to a device, which is to be utilized in conjunction with a constantly driven part of the automobile, and in carrying out the invention, I propose to install the novel circuit closing device, in the speedometer line at an appropriate point between the operating wheel therefor and the meter on the instrument board.

'Ihe improved circuit closing device is preferably in the form of a speed controlled governor which is active on a circuit closing element, cooperating with one of several electric circuit contacts, according to the speed at which the vehicle is driven. For its novelty, the invention relates more particularly to the `specific construction of the governor and the casing in which it Ais confined.

'Ihere are other features of the invention, and these will become apparent as the description goes on.

In the accompanying drawing, forming a part of this application, and in which like numerals are employed to designate like parts throughout the same;

Figure 1 represents a view, partly in section and partly in elevation, of the speed controlled circuit closing device.

Figure 2 shows an elevational view of a lamp box or signal used in conjunction with said device.

Figure 3 is a diagrammatic view of the wiring.

Directing attention first to the speed controlled circuit closing device, appearing in Figure 1, it will be seen that the same comprises a suitably shaped casing including an open ended cylinder 1 closed at its opposite ends by plates 2 and 3 respectively. The plate 2 is provided with an externally disposed screw threaded socket 4, at the bottom of which is a centrally disposed opening. The plate 3 is formed with a similar socket 5. Extending through the opening in the socket is a rota-ry driven shaft 6. This shaft is provided on its upper end with the head 7, located in the socket 4 and provided with a groove forming a key way.

'Ihe opposite'end of the shaft is formed with a head 8 located in the socket 5 and provided`with a key 9. The key Way in the head 7 is adapted to receive the key 10, carried by the flexible driven shaft 11. The shaft 11 may be that of the automobile speedometer. As is usual, it is provided withy the exible casing 12, and in the prescntinstance, the casing is equipped with a coupling 13 to thread onto the socket 4. As above intimated, the governor is keyed or otherwise fixedly connected to the shaft 6 and is disposed Within the casing. The gov ernor comprises a hea-d 14 carrying the l.- Shaped weighted arms 15. As is customary, the weighted ends of the arms are connected together by one or more coil springs, to resist the outward swinging movement. In the present instance, the inner reduced extremities of the laterally extended ends of the governor arms are received in a peripheral groove formed in the head 16 of a sliding sleeve 17, mounted on the shaft. At its top, the sleeve 17 is provided with a flange 18, and interposed between this Bange and the closing plate 2 is a coiled spring 19. rIhe plate 2 is provided with an inte-rnal depending cylindrical guide 20, and the spring 19 is confined therein, while the ange 18 is likewise confined and slidable. There are three electrical contacts 21, fitted in insulation blocks carried by the guide 20. Obviously, the flange 18 is adapted to successively engage these contacts for closing the electric circuit seen in Figure 3. In this same iigure, the reference character 22 represents the coupling carried by the casing of the speedometer shaft on the lower end of the device, this coupling being connected to the socket 5. At this end, the flexible shaft is provided with ahead 23 having a key way for reception of the key 9 on the head 8. If desired, the casing mayl be provided with a removable plug 24, to permit insertion of a lubricant.

As before stated, Figure 2,represents a suitably constructed lamp box v'25. To accord with my invention, this box will be equi ped with separate windows containin the lnscriptions Fast, Slow and Stop In Figure 3 I have shown the co-ntacts 21 vincluded in t-he electric circuit leading to the li hts 26, 27, and 28, adapted to be containe within the compartment of the lamp box 25. 29 represents a suitable switch. 30 indicates a battery which is in electrical connection with the sliding sleeve 17 already referred to. In connection with this figure I might point out that the light 26 may be in the upper compartment of the box 25, the light 27 in the middle compartment, a'nd the light 28 in the lower compartment. Obviously, as the shaft 6 is rotated by the flexible shaft of the speedometer, the governor will serve to raise or lower the sleeve 17 according to the speed of rotation of the shaft. Steady movement of the sleeve 17 is insured, by the action of the spring 19. When the flange 18 on the sleeve is in engagement with the lower contact, the word Stop will be shown. As the speed increases, the sleeve will be lifted, and the ange will come into contact with the middle contact, thus showing the word Slow. When the speed is abnormal, the circuit containing the lremainin contacts will be closed to show the word (C ast.

A. device of the class described comprising a casing embodying an open ended cylinder, closing plates for the opposite ends of said cylinder, one of said plates being provided with internal and external sockets, the other plate being formed with an external socket, a rotary shaft extending through the casino' and having heads on its opposite ends Iocated in said external sockets, a plurality of relatively stationary contacts mounted uponthe wall of the internal socket, a sleeve slidably mounted upon said shaft, said sleeve having a flange at one end coopera-ble -with said contacts and having a grooved collar at its opposite end, a coil spring located in said internal socket and surrounding the shaft and bearing at one end against said flange, and a speed controlled centrifugal governor fixedly mounted upon said shaft within said casing, said governor having spring pressed L-shaped arms, the short inturned ends of which extend into the groove in said collar.

In testimony whereof I affix my signature.1

HAROLD E. CURTISS. 

